CVE-2026-79736: Dell Secure Connect Gateway Auth Bypass

CVE-2026-79736 Overview

CVE-2026-79736 is an Improper Certificate Validation vulnerability [CWE-295] affecting Dell Secure Connect Gateway (SCG) 5.0. The flaw exists in Dell SCG 5.0 Appliance versions prior to 5.36.00.16 and Dell SCG 5.0 Application versions prior to 5.36.00.00. An unauthenticated remote attacker who can position themselves in the network path could exploit the weak certificate validation logic to gain unauthorized access to protected data in transit. Dell published the fix in security advisory DSA-2026-382.

Critical Impact
An unauthenticated remote attacker capable of intercepting SCG traffic can bypass certificate validation and access confidential information exchanged with the gateway.

Affected Products

Dell Secure Connect Gateway 5.0 Appliance versions prior to 5.36.00.16
Dell Secure Connect Gateway 5.0 Application versions prior to 5.36.00.00
Dell Secure Connect Gateway Virtual Edition (per DSA-2026-382)

Discovery Timeline

2026-09-09 - CVE CVE-2026-79736 published to NVD
2026-09-09 - Last updated in NVD database

Technical Details for CVE-2026-79736

Vulnerability Analysis

Dell Secure Connect Gateway brokers remote support connectivity between customer infrastructure and Dell backend services. The affected versions perform Transport Layer Security (TLS) certificate validation incorrectly, allowing a peer presenting an untrusted or forged certificate to be accepted as legitimate. Because the validation error occurs before mutual trust is established, no prior authentication is required to trigger the flawed code path. An attacker positioned between the SCG appliance and a peer endpoint can intercept, observe, or manipulate traffic that was expected to be cryptographically protected. The impact is limited to confidentiality per the published CVSS vector, with no integrity or availability effect noted by the vendor.

Root Cause

The defect maps to CWE-295: Improper Certificate Validation. SCG accepts certificates without correctly verifying attributes such as the trust chain, hostname, or expiration state. Dell has not publicly disclosed the exact validation step that fails.

Attack Vector

Exploitation requires network adjacency to SCG traffic and the ability to present a crafted certificate during a TLS handshake. The high attack complexity reflects the need for a man-in-the-middle position or DNS/routing manipulation. No user interaction or credentials are required.

No verified proof-of-concept code is publicly available for CVE-2026-79736.
Refer to Dell advisory DSA-2026-382 for vendor-supplied technical context.

Detection Methods for CVE-2026-79736

Indicators of Compromise

Unexpected TLS certificates presented to or by the SCG appliance, especially certificates signed by unknown certificate authorities.
SCG connection logs showing successful sessions to endpoints not matching Dell's published support infrastructure.
Anomalous outbound traffic from the SCG appliance to hosts outside Dell's expected address space.

Detection Strategies

Inventory all SCG 5.0 Appliance and Application instances and compare installed versions against the fixed builds 5.36.00.16 and 5.36.00.00.
Inspect network telemetry between SCG appliances and Dell backend services for certificate mismatches, unexpected certificate authorities, or repeated handshake anomalies.
Enable full packet capture on management VLANs hosting SCG for retrospective TLS analysis.

Monitoring Recommendations

Forward SCG appliance logs and network flow data to a centralized analytics platform for correlation.
Alert on new or changing certificate fingerprints observed on SCG communication paths.
Monitor for privileged access or configuration changes on SCG appliances following any suspicious TLS event.

How to Mitigate CVE-2026-79736

Immediate Actions Required

Upgrade Dell SCG 5.0 Appliance to version 5.36.00.16 or later.
Upgrade Dell SCG 5.0 Application to version 5.36.00.00 or later.
Restrict network paths to and from SCG appliances to known Dell endpoints and trusted administrative networks only.
Rotate any credentials or secrets that traversed SCG during the exposure window as a precaution.

Patch Information

Dell addressed CVE-2026-79736 in security advisory DSA-2026-382 – Security Update for Dell Secure Connect Gateway Virtual Edition. Fixed builds are 5.36.00.16 (Appliance) and 5.36.00.00 (Application). Apply the update through Dell's standard SCG update workflow.

Workarounds

No official workaround has been published by Dell; patching is the required remediation.
Until patches are applied, place SCG behind strict egress filtering that permits only Dell's documented backend hostnames and IP ranges.
Terminate SCG traffic through a TLS-inspecting proxy that enforces stricter certificate validation than the appliance itself.

bash

# Verify installed SCG version prior to patch validation
cat /etc/scg/version.conf 2>/dev/null || scgctl --version

# Example egress restriction pattern (iptables) limiting SCG to Dell endpoints
iptables -A OUTPUT -o eth0 -p tcp --dport 443 -d <dell-endpoint-range> -j ACCEPT
iptables -A OUTPUT -o eth0 -p tcp --dport 443 -j DROP